Thursday, September 13, 2018

How Sweden's Election Changed the Map

Sweden's national public television broadcaster Sveriges Television has created an interesting data visualization of the votes cast in this week's Swedish election. It has mapped the overall winner in each election constituency to show where each political party won the most votes.

In the Swedish Vote each constituency is shown as a colored dot. The color of each dot represents the political party that received the most votes in that constituency. Using a dot to represent each constituency means that SVT quickly encounter a familiar problem when creating election maps. Sweden’s population is concentrated in the biggest cities. It is therefore harder to see all of the dots representing the constituencies in the tightly packed urban areas than it is to see the more spread apart dots representing the more rural constituencies.

SVT overcome this problem by changing the shape of the map. In order to make the election results more legible the broadcaster reshapes the country so that all the dots are easier to see. In other words data literacy has been improved at the expense of geographical accuracy. The resulting unfamiliar geography is partly overcome by animating between the more geographically correct map and the new cartogram.

This animating of the dots representing each constituency continues as you progress through the Swedish Vote. Later the dots are rearranged into a grid to show more clearly the number of constituencies won by each party. This grid and the cartogram are also repeated for the results of the 2014 election so that readers can compare the result of this year's election with Sweden's previous election.